11,533 research outputs found
Neutrino quasielastic interaction and nuclear dynamics
We investigate the double differential neutrino-carbon quasielastic cross
sections as measured by the MiniBooNE experiment. Our present treatment
incorporates relativistic corrections in the nuclear response functions and
includes the multinucleon component. We confirm our previous conclusion that it
is possible to account for all the data without any modification of the axial
mass. We also introduce the Q^2 distribution for charged and neutral current.
The data point at a sizable multinucleon component beside the genuine
quasielastic peak. They are also indicative of the collective character of the
nuclear response, of interest for hadronic physics.Comment: Two figures added and two figures modifie
Energy reconstruction effects in neutrino oscillation experiments and implications for the analysis
Data on neutrino oscillation often involve reconstructed neutrino energies
while the analysis implies the real neutrino energy. The corrections
corresponding to the transformation from real to reconstructed energy are
discussed in the case of Cherenkov detectors where multinucleon events appear
as quasielastic ones. These corrections show up as a tendency for the events to
escape the region of high flux, with a clear preference for the low energy
side. This is an effect of the multinucleon component of the quasielastic cross
section. We have applied our corrections to the T2K and MiniBooNE data for
electron appearance or disappearance data. We show that the inclusion
of this correction in the analysis is expected to lead to an increase of the
best fit oscillation mass parameters, particularly pronounced for the MiniBooNE
neutrino data. This inclusion in the analysis of the MiniBooNE neutrino data
should improve the compatibility with the existing constraints
Neutrino energy reconstruction problems and neutrino oscillations
We discuss the accuracy of the usual procedure for neutrino energy
reconstruction which is based on the quasielastic kinematics. Our results are
described in terms of a probability distribution for a real neutrino energy
value. Several factors are responsible of the deviations from the reconstructed
value. The main one is the multinucleon component of the neutrino interaction
which in the case of Cherenkov detectors enters as a quasielastic cross
section, increasing the mean neutrino energy which can differ appreciably from
the reconstructed value. As an application we derive, for excess electron
events attributed to the conversion of muon neutrinos, the true neutrino energy
distribution based on the experimental one which is given in terms of the
reconstructed value. The result is a reshaping effect. For MiniBooNE the low
energy peak is suppressed and shifted at higher energies, which may influence
the interpretation in terms of oscillation. For T2K at the Super Kamiokande far
detector the reshaping translates into a narrowing of the energy distribution
Neutrino and antineutrino quasielastic interactions with nuclei
We investigate the interaction of neutrinos and antineutrinos with nuclei. We
explore in particular the role played by the multinucleon excitations which can
contaminate the quasielastic cross section. For neutrinos the multinucleon term
produces a sizable increase of the quasielastic cross section. Part of the
effect arises from tensor correlations. For antineutrinos this influence is
smaller owing to the axial-vector interference which increases the relative
importance of the terms which are not affected by these multinucleon
excitations
Muon capture in the front end of the IDS neutrino factory
We discuss the design of the muon capture front end of the neutrino factory
International Design Study. In the front end, a proton bunch on a target
creates secondary pions that drift into a capture transport channel, decaying
into muons. A sequence of rf cavities forms the resulting muon beams into
strings of bunches of differing energies, aligns the bunches to (nearly) equal
central energies, and initiates ionization cooling. The muons are then
accelerated to high energy where their decays provide neutrino beams. For the
International Design Study (IDS), a baseline design must be developed and
optimized for an engineering and cost study. We present a baseline design that
can be used to establish the scope of a future neutrino Factory facility.Comment: 3 pp. 1st International Particle Accelerator Conference: IPAC'10,
23-28 May 2010: Kyoto, Japa
Multiparticle Quantum Superposition and Stimulated Entanglement by Parity Selective Amplification of Entangled States
A multiparticle quantum superposition state has been generated by a novel
phase-selective parametric amplifier of an entangled two-photon state. This
realization is expected to open a new field of investigations on the
persistence of the validity of the standard quantum theory for systems of
increasing complexity, in a quasi decoherence-free environment. Because of its
nonlocal structure the new system is expected to play a relevant role in the
modern endeavor on quantum information and in the basic physics of
entanglement.Comment: 13 pages and 3 figure
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